1. Technical Field
The present invention generally relates to a plasma display panel (PDP) which includes an electromagnetic wave shielding layer.
2. Related Art
A plasma display device comprises a front case that includes a perimeter unit defining a window, an electromagnetic wave shielding filter that covers the window, a conductive filter holder which presses the electromagnetic wave shielding filter against the perimeter unit of the front case and which is fixed to a coupling boss of the front case, a plasma display panel (PDP) which includes a front panel and a rear panel and which is disposed on a rear of the conductive filter holder, a chassis that supports the PDP, connecting cables which connect a circuit unit that drives the PDP and is disposed on a rear of the chassis and the PDP, and a rear case which is coupled to the front case and which is disposed on a rear of the chassis. A thermal conductive sheet is interposed between the PDP and the chassis.
The front panel comprises a front substrate, a plurality of sustaining electrode pairs that include Y electrodes and X electrodes formed on a rear surface of the front substrate, a front dielectric layer that covers the sustaining electrode pairs, and a protection layer that covers the front dielectric layer. Each of the Y electrodes and the X electrodes includes a transparent electrode formed of indium tin oxide (ITO) and bus electrodes formed of a metal having high conductivity. The bus electrodes are connected to the connecting cables disposed on left and right sides of the PDP.
The rear panel comprises a rear substrate, a plurality of address electrodes which are formed to cross the sustaining electrode pairs and which are disposed on a front surface of the rear substrate, a rear dielectric layer that covers the address electrodes, a plurality of barrier ribs which define the discharge cells and which are disposed on the rear dielectric layer, and a plurality of fluorescent layers disposed in the discharge cells. The address electrodes are connected to connecting cables disposed on upper and lower parts of the PDP.
An electromagnetic wave shielding filter comprises a central unit that faces the window of the front case and a perimeter unit that surrounds the central unit. A conductive mesh layer for shielding electromagnetic waves is formed on the central unit. A metal layer for electrically connecting the conductive mesh layer to the conductive filter holder is formed on the perimeter unit. The conductive mesh layer is formed on a transparent substrate and is covered by a planarizing layer. A near infrared ray shielding layer is formed on the planarizing layer. The energy of the electromagnetic wave trapped by the conductive mesh layer is transmitted to the far side of the PDP or is dissipated to the outside of the PDP via the metal layer and the conductive filter holder.
However, in the case of a PDP having the above structure, there is a drawback in that the manufacturing cost is increased because the electromagnetic wave shielding filter and the conductive filter holder can only be coupled to the front case after being manufactured separately.
Also, a predetermined space is formed between the electromagnetic wave shielding filter and the PDP due to the thickness of the conductive filter holder, and a portion of the heat generated in the PDP due to discharge is transferred to this space.
However, the air in this space is not circulated because the space is surrounded by the conductive filter holder. An air pathway can be formed by modifying the shape of the conductive filter holder, but constructing an air pathway large enough to circulate the air is difficult. Even though a sufficiently large enough pathway is secured, the efficient dissipation of heat by air convection in the space cannot be achieved because there is tremendous air friction due to a narrow gap, that is, the thickness of the conductive filter holder, between the electromagnetic wave shielding filter and the PDP.